Method and apparatus for opening envelopes



June 11, 1957 W. T. KENNEL METHOD AND APPARATUS FOR OPENING ENVELOPESFiled Sept. 13, 1954 IIIIIIIIIIIIIIIII'IIII IIIIIIIJ INVENTOR. WillardT. Kennel United States Patent 1 METHOD AND APPARATUS FOR OPENINGENVELOPES The present invention is a method of and apparatus for openingenvelopes.

One object of the invention lies in the provision of a method of openingenvelopes which eliminates the possi bility of tearing. or cutting thecontents thereof.

Another object of the invention lies in the provision of a method of andapparatus for opening envelopes which enables one to open envelopes bythe use of one hand only.

Another object of the invention'lies in the provision of a letter openerwhich is automatically actuable, thus 'providing trouble free means foropening envelopes.

Other objects of the invention are to provide a letter opener of thecharacter described which will be comparatively simple in construction,strong, durable, highly efiicient and reliable in use, compact, andwhich may be manufactured at low cost.

-'All of the'foregoing and other objects of the invention will becomeapparent from a study of the following specification taken in connectionwith the accompanying drawings wherein like characters of referencedesignate corresponding parts throughout the several views and wherein apreferred form of the invention is shown.

It should be understood however that the drawings and description areillustrative only and are not intended to limit the invention exceptinsofar as it is limited by the claim.

In the drawings,

Figure 1 is a perspective view of the base of a lamp within which theletter opener constituting the subject matter of this invention isdisposed;

Figure 2 is a transverse Vertical cross section as at line 22 of Figure1; and,

Figure 3 is a fragmentary skeletal perspective view of the cooperatingshearing and actuating elements of the a letter opener.

Referring now more particularly to the drawings, the disclosedembodiment of the invention comprises a frame indicated in general bythe numeral 10 which includes a decorative housing 11 having front,side, back and top walls 12, 13, 14 and 15 adapted to cover a removablebody portion 16 having a bottom wall 17 and an upwardly spacedhorizontal intermediate partition 18 supported on vertical side panels19 carried by the bottom wall 17.

In the disclosed embodiment of the invention we show a pair of verticalstandards 50 which are adapted to support a lamp (not shown) and areinternally threaded at their lower ends at 51 to receive a headed bolt52 which is adapted to releasably secure the body portion 16 within thehousing 11.

A conventional electric motor 20 is supported on a side panel 19 and hasits driving shaft 21 connected to a suitable speed reduction motiontransmission indicated in general by the numeral 22. The reductiontransmission is here shown to be a worm and gear combination but it willbe understood that any one of many conventional transmissions may beemployed. An additional motion transmitting device such as a belt orchain 23 transmits Patented June 11,

the rotary motion from the transmission 22 to the rotatable element 24.

Rotatable element 24 is journaled at its ends on opposed side panels 19and is provided with a cylindrical peripheral face 25 which is disposedspaced from a shear bar 26. The face of the element 24 may be spacedfrom the cutting edge 27 of the shear bar 26 any desired distance,however, for the most practical application of the invention it isdesired that this spacing be substantially equal to the paper thicknessforming the body of an envelope to be opened thereby. It is necessarythat this spacing be at least equal to this thickness to insure openingof the envelope and is preferable that the spacing be greater than thepaper thickness of the envelope body but not so great as to be liable topermit sufficient overhang of the envelope to include a portion of itscontents which may extend beyond the cutting edge 27 of the shear bar26.

A shearing blade 28 is spirally arranged'on the peripheral face 25 ofthe rotatable element 24 and extends the full length of the element 24and substantially 270 degrees of its circumference leavingsubstantially'90 degrees of its circumference clear to form a stopagainst which the edge of an envelope placed with its marginal edgeportion extending over the shear bar 26 may strike to limit the overhangthereof. the blade 28 is substantially the same as the spacing betweenthe face 25 and the shearing edge 27 of shear bar 26 so that when theelement 24 is rotated the shearing blade 28 cooperates with the shearbar 26 to shear off the marginal edge portion of an envelope extendingbeyond the shear bar 26.

A supporting plate 29 is carried by front panel 19 and extends at rightangles to the shear bar 26 forming a smooth surface upon which theenvelope to be opened may be slid into position on the shear bar 26. Thehousing 11 is provided in its front wall 12 with an elongated slot oropening 30 through which an envelope may be inserted into the letteropening mechanism and the slot 30 opens onto the upper surface of theplate 29 to properly guide movement of the envelope to an openingposition on the shear bar 26 with its forward edge impinging against theperipheral face 25 of the element 24. It is then only necessary torotate element 24 one revolution whereupon the edge of the envelope issheared oil, open ing the envelope.

To provide means for energizing the prime mover 230 i provide anenergizer or actuating mechanism 31 which is seen to consist of avertically tiltable table 32 journaled at 33 on a vertically disposedplate 34 and the table supports a mercury or other type normally openelectric switch 35 which forms a part of the electric circuit includingthe prime mover or electric motor 24}. As viewed in Figure 2 the switch35 is disposed in its normally open position and upon insertion of anenvelope through the slot 30 the pressure of the envelope depresses adepressible resilient element 36 which is operably connected at 37 tothe tiltable table 32. To eliminate the possibility of the resilientelement 36 lifting the envelope as it is inserted through the slot 30 Iprovide one or more resilient fingers 38 carried by the housing 11 andyieldably resting upon the plate 29 thereby maintaining the envelopeflat upon the plate 29 and insuring its proper positioning against theperipheral face 25 of the element 24. When the envelope is inserted itdepresses element 36 which actuates switch 35 energizing motor 20 whichthrough the transmission elements 22 and 23 rotates the rotatableelement 24 and shears the edge from an en velope bearing against theperipheral face 25. As long as the envelope is disposed in a position todepress the element 36 the motor continues to operate and the element 24continues to rotate. However, when the envelope is removed the switch 35is raised by means of the Obviously the depth of- 3 resilient element 36and connection to the motor 20 is broken.

To permit proper positioning of an envelope to be opened it is necessarythat the rotatable element 24 be stopped in a position wherein theshearing blade 28 is disposed away from the shear bar 26 thus presentingan unobstructed, area of the peripheral face 25 toward the shear bar 26.

Since it is necessary that the rotatable element 24 al ways stop in aposition with the shearing blade 28 disposed away from the shear bar 26I have provided at one end on the element 24 a cam 39 which is adaptedto actuate a cam follower 40 carried by a rotatable rod 41 having a bellcrank lever 42 at its opposed end. When the rotatable element 24 isdisposed in proper position the cut away portion 39' of cam ,39 releasesthe cam follower 40 which permits counter rotation of rod 41 andsimultaneous release of the rockable table 32 thus automatically openingswitch 35. However, when the shear ing blade 28 is disposed in shearingrelation to the shear bar 26 the cam 39 depresses follower 40 rotatingrod 41 causing the bell crank lever 42 to tilt the plate 32 thusactuating switch35 energizing motor 20 until such time as the follower40 is released by the cut away portion 39 whereupon the motor stops withthe rotatable element 24 in proper position to receive a subsequentenvelope.

Having thus described my invention, I claim:

An envelope opener comprising a supporting frame having an accessopening through which an envelope may be inserted into the frame; saidaccess opening extending substantially the full widthof said frame; afixed shear bar coincident in length to said access opening carried bythe frame and disposed to support a marginal edge POT tion of anenvelope inserted into the frame through said access opening; aunidirectional rotatable element coincidental in length to said shearbar and having an annular peripheral face disposed spaced from saidshear bar and constituting a stop against which the edge of saidenvelope strikes to limit the amount of marginal edge portion extendingover the shear bar; a shearing blade spirally car ried by said elementand extending substantially the full length of said shear bar andterminating short of traversing the full circumference of said elementand disposed to cooperate with said shear bar upon rotation of saidelement for shearing said marginal edge portion from said envelope; anelectric motor operably connected for rotating said element; an electriccircuit connected with said element and including a normally openswitch; weight depressible means for actuating said switch and operableupon insertion of an envelope through said access opening; cam meansassociated with said rotating element for actuating said switch whensaid shearing blade is disposed in cooperating relation to said shearbar and adapted to release said switch when said shearing blade departsfrom said shear bar whereby to stop rotation of said rotatable elementwith said shearing blade removed from said shear bar.

References Cited in the file of this patent UNITED STATES PATENTS530,920 Blomgren Dec. 18, 1894' 1,265,844 Washburne May 14, 19181,302,398 Mangini Apr. 29, 1919 1,814,586 Crosby July 14, 1931 2,099,230Rix Nov. 16, 1937 2,589,347 Demerath Mar. 18, 1952 2,596,467 Buckens May13, 1952 2,656,889 Kaplan Oct. 27, 1953 FOREIGN PATENTS 621,186 GreatBritain Apr. 5, 1949

